Field of the Invention
The present invention relates to an apparatus of producing cement clinker by burning cement raw material in a kiln while supplying to a preheater.
Priority is claimed on Japanese Patent Application No. 2012-187322, filed Aug. 28, 2012, the content of which is incorporated herein by reference.
Description of the Related Art
In a cement production apparatus, a preheater is provided for pre-heating cement raw material. The preheater is configured by a plurality of cyclones connected in a vertical direction in which the cyclone at a lowermost stage is connected to a kiln inlet part of a cement kiln. The cement raw material is pulverized by a mill, and then is supplied to the preheater from a duct connecting the cyclone at a top stage and the cyclone at a lower stage at a middle position of the preheater. In the preheater, the cement raw material is introduced into the cyclone at the top stage being carried by exhaust gas rising from the cement kiln, then fallen into each of the cyclones sequentially so as to be pre-heated by a heat of the exhaust gas, and finally supplied to the cement kiln from the cyclone at the lowermost stage.
When the cement raw material is supplied to the duct, since the plurality of cyclones are provided above the duct, it is necessary to supply the material equally in order to pre-heat equally in the cyclones.
As an apparatus which supplies powder such as the cement raw material, there are apparatuses described in Patent Document 1 to Patent Document 3 in which improvement of dispersibility is contrived.
In an apparatus described in Patent Document 1, on an upper surface of a lower-end part of a bottom plate of a material-supplying pipe (i.e., an inclined chute) supplying powder of cement raw material, a mountain-shape protruded part protruding as a probability curve is formed. The protruded part is formed so that a highest part is at a lower-end side and a height at an upper-stream side is zero, so that the material is supplied into a duct being divided to left-and-right by hitting against the protruded part.
In Patent Document 2, a dispersing device of powder material is proposed in which a dispersing plate is provided at a connecting part between a material-supplying pipe (i.e., a charge chute) and a duct (i.e., a duct) so as to be protruded to a half of an inner diameter of the charge chute at a maximum by angular-displacement around a horizontal axis. In Patent Document 3, a device in which a material-slide surface is formed in substantially orthogonal direction to a gas flow at a connecting part between a material-supplying pipe (i.e., a material chute) and a duct (i.e., a heated-gas duct) is disclosed. In Patent Document 4, a device in which a dispersing plate is protruded in a duct is disclosed.
In the devices disclosed in Patent Documents 2 to 4, the material is supplied with being dispersed into the duct by hitting against the dispersing plate protruding in the duct or the material-side surface. In Patent Document 5, a device in which a material-dispersion box is provided at a connecting part between a material-supplying pipe and a duct for dispersing and repelling material which falls in a material chute is disclosed.